Film mounting assembly



July 2l, 1964 T. P. ANDERSON ETAL FILM MOUNTING ASSEMBLY Filed March l2, 1962 2 Sheets-Shes?l 1 July 21, 1964 T. P. ANDERSON ETAL 3,141,276

FILM MOUNTING ASSEMBLY 2 Sheets-Sheet 2 Filed March l2, 1962 Flr/5554,

W AT-T0RNEYS United States Patent Ofi 3,141,276 Patented July 21, 1964 3,141,276 FILM MOUNTING ASSEMBLY Thomas P. Anderson, Winnetka, and Robert Beispel, Chicago, Ill., assignors to Microseal Corporation, Chicago, Ill., a corporation of Illinois Filed Mar. 12, 1962, Ser. No. 178,792 3 Claims. (Cl. 53-123) This invention relates to a method and apparatus for cutting small film pieces from an elongated film strip and for effecting the insertion of the film pieces into film pockets formed within microfilm record cards.

With the ever increasing use of microfilm records and statistical cards in conjunction with one another, it has become desirable to provide a means for mouting microfilm directly on such a statistical card. We have devised a record card having an aperture formed therein which has transparent enveloping members or sheets disposed on opposite sides of the card and overlying the aperture. The sheets, if rectangular in configuration, have three edges thereof secured to the opposed surfaces of the card by means of suitable adhesive materials or the like Which are placed on the card along the edges of the apertures but the fourth edges thereof are not sealed to the card although they do overlie the card (that is, that edge of each sheet does not terminate at the edge of the aperture). A microfilm strip can be maintained in the pocket formed intermediate the enveloping members or between one surface of the card and an adjacent enveloping member.

If the film strip is translucent and the enveloping members are transparent, the film strip may be viewed while still mounted on the record card since light may be transmitted through the transparent enveloping members. Thus, projectors can be arranged to accept such record cards so that the image on the film strip contained within a card can be projected on a screen to enlarge the image without necessitating the removal of the film strip from its mounted position on the record card.

We have devised other record cards having only a single enveloping member arranged so that the film strip can be maintained in a pocket formed between a portion of the card surface lying around the aperture and the enveloping member. In any case, some film pocket is formed by the enveloping member or members.

While the insertion of two or three film strip pieces into the lm pockets in a like number of cards can be effected by hand, it is manifest that in those situations in which large numbers of film pieces must be card mounted, the hand mounting procedure is not practicable. Furthermore, hand mounting film pieces within record card film pockets is time consuming and may cause fingerprints or stains to appear on the film which would blur the image formed thereon when that image is projected on a screen.

Our invention is directed to a method and apparatus for cutting film pieces from an elongated film strip and inserting those film pieces into the film pockets formed in a multiplicity of cards. Basically, our invention consists in the provision of a supporting stand having a film bed and a card bed formed thereon and to a means for cutting the film strip to form film pieces of a desired length and to a means for feeding a film piece so cut along the film bed and onto the surface of a card mounted on the card bed and thence into the film pocket formed Within the card.

It will be understood by those skilled in this art that microfilm which is presently being produced is formed in a standard size and configuration. The microfilm strip is generally quite long and has a plurality of rectangular images formed thereon which are spaced apart two inches on center with an integral joining strip portion formed intermediate each of the images. Many microfilm record cards have been formed so as to receive a standard film piece of normal width and two inches in length. We have devised a film feeding assembly for effecting the insertion of such film pieces into record cards. It will be understood however that in addition to carrying the film piece, film record cards are used to store considerable data. Such data storing is effected by punching the record card in a particular manner or by applying magnetic or electrosensitive inks on one or both faces of the card in that area of the card not taken up by the film pocket. A good many quantity users of film record cards have expressed a desire to store more data on film record cards. Since storage facilities and automatic sorting machines are adapted to receive standard sized record cards the answer seemed to lie in reducing the size of the aperture in the record card. For this reason a number of quantity card users have required that the film pocket or aperture formed in the record card be no greater in length than 1.90 inches. Since the length of the image formed on a standard microfilm roll is less than 1.9 inches the record card apertures were reduced in length accordingly and film pieces were cut from microfilm strips so that the length o-f each film piece was 1.9 inches or less or else the strips were applied to the cards in overlapping relation. This could be done without in any way cutting off or destroying any part of the image on the film strip. The reduction in size of the desired film piece did however present a considerable problem in pocket forming record cards in connection with the means for cutting lm pieces from a film strip and inserting them into the record card pockets.

Since the images on a film strip are spaced apart two inches on center two cutting operations were required prior to insertion of the shortened film piece into the record card pocket. This double cutting operation considerably lengthens the time required to mount a multiplicity of film pieces into a like number of record cards.

The film mounting assembly which we have devised is effective to cut out a slug of the desired length (for instance, 020 inch) from the integral image joining portion of an ordinary microfilm strip between adjacent images on that strip in a single operation. Still further, we have devised a film mounting assembly which can effect the removal of this slug and will then act to push the film piece of the desired cut length into a record card pocket.

The film and card beds are each substantially flat and the card bed lies in a plane displaced slightly below the horizontal film bed. In fact, the card bed is recessed from the plane of the film bed a distance approximately equal to the thickness of record cards so that the upper card surface is substantially coplanar with the film bed. A guide member is associated with the card Ibed so as to guide a card onto the bed so that the film pocket formed within the card will be aligned with the film bed. A shoulder interconnects the film and card beds and the card is placed on the card bed with one edge thereof in engagement with this shoulder.

A roll of microfilm is rotatably mounted on one end of the support and means are provided for moving the film strip along the film bed and thence onto the upper surface of the card and thence into the film pocket within the card. In order to keep the microfilm strip flattened against the film bed as it travels along that bed overhanging guide plates are provided which overlie the film bed and an adjacent portion of the card bed. That portion of the cover plate overlying the card bed also, of course, tends to keep the record card flattened against the card bed.

A pair of elongated apertures or slits are formed within the support transversely through the film bed and slitter knives or cutting blades are movable therethrough. A burst-cutting block completely overlies the rearwardmost aperture formed within the film bed and the cutting edge of the slitter knife positioned therein passes through the aperture from beneath the film bed and into engagement with the block to cut a film strip piece from the film strip. A shear-cutting block is positioned over the film bed adjacent the forwardmost aperture and has a concave arcuately chamfered edge formed therealong. The slitter knife within the forwardmost aperture passes through that aperture from beneath the fihn bed simultaneously with the other knife and moves in sliding engagement along a side of the block adjacent the arcuately chamfered concave edge of the shear-cutting block to cut the film by a shearing action.

The film strip is normally stored in a roll and has a natural tendency to curl in one direction. This film strip is fed onto the film bed so that the film tends to curl toward the bed. We have found that by feeding the film strip through the assembly in this manner, cutting of the film strip, removal of the film strip slug, and insertion of the film piece into a record card pocket is greatly facilitated.

Assuming for a moment that a record card is positioned on the card bed and that a film strip is lying in the film bed with its leading edge extending 0.20 inch past the forwardmost aperture, and that the slitter knives are spaced apart a distance of 1.90 inches, simultaneous actuation of the slitter knives will act to cut a film piece 1.90 inches in length from the film strip. The rearwardmost slitter knife will effect a burst-cut while the forwardmost slitter knife will cut the film strip by shear. Due to the manner in which the film strip is placed upon the film bed and the configuration of the shear-cutting block, the remaining film strip slug 0.20 inch in length will fly upwardly and outwardly a distance of several inches in each direction. Subsequently, by moving the film strip along the film bed in a forward direction, the leading edge of the rolled film strip will act against the rearward edge of the film piece and push the film piece onto the upper surface of the record card and thence into the film pocket. Separate means need not be provided therefore for effecting insertion of the film piece into the film pocket.

A film mounting assembly of the type generally described above is illustrated in the appended drawings. Note should however be made of the fact that other variations of this arrangement are within the scope of our invention.

For instance, if suitable guide means are provided for the fihn as it passes through the assembly between the cutters, the rearwardmost slitter and block can be arranged to effect a shear cut. Still further, other but less effective means can be employed for cutting the film strip at the forward end of the film feed assembly. A con- Vex shear cutting block or a convex or concave blade edge in cooperation with a differently configurated cutting block might be effectively employed. A straight-edged slitter and a flat but angularly oriented cooperating block will also act to force the cut slug to fly out of the immediate cutting vicinity.

It is therefore a principal object of this invention to provide a means and method for cutting a film strip piece of a desired length from an elongated film strip and for effecting the insertion of the microfilm piece into the film pocket of a record card.

An important feature of the invention resides in the provision of means for cutting film strip pieces from a film piece in lengths less than the center-to-center dimension between adjacent images on the film strip in a single operation wherein a film strip slug is expelled from the film bed simultaneously with the cutting operation.

These and other objects of the invention will become apparent from time to time as the following specification proceeds and with reference to the accompanying drawings, wherein:

FIGURE 1 is a side elevational View of a film feeding mechanism constructed in accordance with the principles of our invention;

FIGURE 2 is a plan view of the film feeding mechanism illustrated in FIGURE l;

FIGURE 3 is a vertical sectional View through the shear-cutting block and taken along lines III-III of FIG- URE 2;

FIGURE 4 is a vertical sectional view taken longitudinally through a portion of the film feeding mechanism illustrated in FIGURES l and 2 and showing some parts in vertical section and others in side elevation;

FIGURE 5 is a transverse vertical sectional view through the assembly of FIGURE 4 taken along lines V-V of FIGURE 4;

FIGURE 6 is a transverse vertical sectional view taken through the assembly of FIGURE 4 and along lines VI-VI thereof; and

FIGURE 7 is an end view in elevation of a portion of the shear-cutting block.

The film feed mechanism illustrated in the drawings comprises a support 10 including a base 11 and a pair of spaced Vertical side Walls 12. An upper plate 13 of the support 10' has an elongated recess comprising a film bed 14 formed therealong which is adapted to receive a microfilm strip such as the strip 15. The side walls 16 of the film bed act as guides to guide the film strip 15 through the film bed to thereby form a lm channel for directing a film strip through the assembly and are spaced apart a distance approximately equal to the width of the film strip 15.

The film strip 15 is wound on a spool 16 which, in turn, is rotatably mounted on a pin 17 extending outwardly from a rearwardly extending leg 18 which is connected to the support 10 by screws 19. The inner side wall 20 of the leg 1S is disposed in coplanar relation with one of the side walls of the film channel to serve as an additional guideway for guiding the film strip into and through the film bed 14. A guide block 21 is secured to the upper plate 13 by screws 22 and has its inner surface spaced from the inner surface 20 of the leg 18 a distance approximately equal to the width of the film strip 15 and in coplanar relation with the opposite side wall of the film channel. A shaft 23 has one end journalled in the guide block 21 and its opposite end journalled in the leg 18 and has a roller 24 formed of rubber or a rubber-like material mounted thereon which, in turn, has a protruding annular bead 24a extending circumferentially therearound. The roller is maintained in a fixed position on the shaft 23 between the leg 18 and the blocks 21 by means of spacers 25.

A shaft 26 is likewise journalled within the vertical side walls 12 at a point spaced directly below the shaft 23 and beneath the plate 13 and has a roller 27 with a protruding annular bead 27a formed about the roller, similar to the roller 24 mounted thereon. The plate 13 is apertured as at 28 and the protruding annular bead 27a on the roller 27 is of sufficient diameter to extend up into this aperture. The annular bead 24a of the roller 24 contacts the annular bead 27a at the aperture 28 and this point of contact is disposed in the same plane as thel plane of the film bed 14.

It will be observed that the spool 16a is mounted on the spindle 17 so that the film strip 15 extends from the top of the spool to the point of contact of the roller beads 24a and 27a and onto the lm bed 14. A knob 29 is keyed to the shaft 26 so that clockwise rotation of that knob (as viewed in FIGURE 1) will act to pull the lm strip 15 from the spool 16a and through the rollers and thence onto the film bed 14. The spool 16a will then rotate on the spindle 17 as the film strip is pulled through the rollers.

The opposite end of the plate 13 is recessed somewhat from the plane of the film bed 14 and has a transparent glass or plastic plate 31 mounted thereon, the upper surface of which defines the major portion of a generally horizontal card bed 32, which surface lies in a plane parallel to but spaced slightly below the plane of the film bed 14. In fact, the card hed 32 lies in a plane which is spaced below the plane of the film bed 14 at a distance approximately equal to the thickness of a film record card 33.

The film record card 33 has a rectangular aperture 34 formed therein and transparent enveloping members or sheets 35, which are also rectangular in configuration, mounted on the top and bottom surfaces, respectively, of the card so that they overlie the aperture 34. The enveloping members 35 are mounted over the apertures 34 so that their edges overlie portions of the card defining the aperture but only three edges of each of the enveloping members are secured to the respective top and bottom surfaces of the card. In each case, an unsecured portion (35a) of the enveloping member overlies the card along the edge of the aperture adjacent the nearest end of the card. A slight gap may be formed between the unsecured edges of the enveloping members and the record card although this gap will of course be very small and may not exist at all. In any event, it is at this point that a film strip is inserted between one of the enveloping members and an associated surface of the record card, The card pocket is that space formed intermediate the enveloping members which is defined by the four edges of the aperture. However, it will be understod as has already been pointed out that some cards are arranged with only a single enveloping member and the film is then adapted to be mounted in a pocket formed between that enveloping member and the associated surface of the card.

As illustrated in the drawings, the enveloping members 35 are transparent so that light can be transmitted through those members as well as through the film strip contained within the film pocket if and when it is desired to project the film strip image on a screen so that removal of the film strip from the film pocket for this purpose is not necessitated.

The glass plate 41 forming part of the card bed 32 terminates at a shoulder 36 and a V-grooved depression 37 is formed transversely of the support 10 within the card bed 32 and lies intermediate the shoulder 36 and a shoulder 33 formed at the junction of the film and card beds.

Top plates 4f) and 41 are mounted on the upper plate 13 and have their innermost edges 42 slightly overhanging the film bed 14. The overhanging edges of the top plates are spaced vertically from the surface of the lm bed 14 a distance equal to or only very slightly greater than the thickness of the film to be passed therethrough so that they will be effective to flatten the film on the film bed. Each of the plates 40 and 41 has an arm 43 extending out over the opposite sides of the card bed 32. The outermost ends of the arms 43 are turned upwardly as at 44 so that a record card can be guided into position along the card bed 32 and beneath the arms 43.

A guide block 45 is afiixed to the support 10 and serves to guide a record card into its proper mounted position on the card bed 32 with the longitudinal center axis of the aperture within the card disposed coincident with a center line of the film bed 14.

The spacing between the major flat portion of the card bed 32 and the undersurface of the arms 43 is approximately equal to the combined thicknesses of the record card and the film strip 15 (the edges of the enveloping members having negligible thickness) and the card bed 32 lies in a plane spaced from the plane of the film bed 14 a distance approximately equal to the thickness of the record card itself so that the upper surface of the record card lies substantially coplanar with the film bed 14.

A record card can be inserted into the space between the arms 43 and the card bed and will be guided into position by the guide block 45 and can be moved into engagement with the shoulder 38. Rotation of the knob 29 will move the film strip 15 through the film bed and thence past the shoulder 38 and onto the upper surface of the record card. Further rotation of the knob 29 will move the leading or free edge of the microfilm along the upper surface of the record card and thence between the upper enveloping member 35 and the card surface and into the film pocket.

Applicants principal contribution resides in the method and means for cutting and inserting film in the manner hereafter described.

As is best shown in FIGURE 4, the upper plate 13 has a pair of apertures or slits 50 and 51 formed therein transversely of the film bed 14. These slits extend entirely across the film bed and are spaced apart a desired distance corresponding to the desired length of the cut film pieces. As has already been indicated, it may be desirable to cut the film strip into film pieces having lengths of 1.9 inches. In such case, the slits 50 and 51 would be spaced apart a distance of 1.9 inches. A resilient cushion 52 is positioned on the undersurface of the plate 13 between the slits 50 and 51. A generally cylindrical member 53 is seated against the undersurface of the cushion 52 and is, in turn, backed by a plate 54 having a concave recess 55 formed therein complementary to the cylindrical member 53 to provide a journal for the member 53. The parts are all maintained in an operative position between the slits 50 and 51 by a plurality of screws 56 extending through the members 54 and 52 and screw threaded into the undersurface of the upper plate 13. A pair of connecting rods 57 extend longitudinally of the plate 13 and are positioned between the cushion 52 and the plate 54. The rods 57 are received within square cut apertures 58 formed transversely through the cylindrical member 53. The slots 58 are flat bottomed so that rotation of the cylindrical member 53 from the position illustrated in FIGURES 4 and 6 will act to urge the rods 57 upwardly against their respective cushions.

Slitter knives or cutting blades 60 and 61 are positioned for sliding movement within the slits 5t) and 51 and are apertured to receive the ends of rods 57 as is illustrated in FIGURES 4 and 5. A handle 62 `is connected to the cylindrical member 53 in the manner shown in FIGURES 1 and 6 and serves to provide a means forl rotating the member 53. It will thus be observed that depression of the handle from the position illustrated in FIGURE l will act to rotate the cylindrical member 53 to move the rods 57 upwardly against their respective cushions. Such upward movement of the rods 57 will act to move the blades 6l) and 61 upwardly within the slits S0 and 51. It is in this manner that a cutting action is achieved.

A burst-cutting block 63 is connected to the upper plate 13 by means of a pair of screws 64 so as to extend entirely across the film bed 14 and has an elongated recess 65 formed therein which is spaced from but positioned in registry with the slit 5t). The recess 65 has a width only slightly greater than the thickness of the Slitter knife 50a so that the knife 50a. can pass upwardly through the slit 5t) and thence into the recess 65 to cut a film strip lying between the block 63 and the surface of the film bed 14. A so-called burst cut is thereby effected and for this reason the block 63 is described as being a burst-cutting block. It should also be noted that a depending portion 66 of the block 63 extends toward the fiat surface of the film bed 14 to assure that a film strip will be flattened against the film bed. The depending portion 66 extends downwardly from the undersurface of the block 63 a distance approximately equal to the thickness of the top plates 40 and 41 and is spaced from the film bed a distance approximately equal to or very slightly greater than the thickness of ordinary microfilm.

A shear-cutting block 68 extends across the film bed 14 and is affixed to the upper plate 13 in the same manner as the block 63. The cutting block 68 however is arranged so that the knife 60 effects a shear cut rather than a burst cut. One corner edge of the block 68 has a concave arcuate chamfer 69 formed therein. This charnfer is best shown in FIGURE 7. FIGURE 3 is a vertical sectional view through the center of the block 68 and shows the formation of the chamfer 69 at that point. The block 68 is so positioned on the upper plate 13 that the edge of the slitter knife 61 will move upwardly along the front face of the block adjacent the chamfer 69.

Assuming that a film strip is lying on the film bed with only a small portion thereof extending forwardly of the aperture 51 (to the right of aperture 51 as viewed in FIGURE 4) upward movement of the slitter knife 61 will act to cut the film strip at its outer longitudinal edges first and will then cut inwardly from those edges until the center of the cutting edge of the slitter knife 61 has moved past the center of the concave arcuate chamfer 69. After having cut through the sides of the microfilm the slitter knife 61 acts like a wedge as it makes its last cut through the center of the film strip and the result is that the small slug or end portion of the film strip flies upwardly and outwardly from the cutting block 68. The inherent tendency of rolled microfilm to curl about both longitudinal and transverse axes aids in causing the cut slug to fiyV from the shear-cutting block 68.

- In operation our device functions substantially as follows: A record card is placed upon the card bed in the manner heretofore described and a film strip is moved along the film bed 14 until the rear edge of an image comes in line with or slightly forward of the slit 50. Since the center-to-center distances between successive images on an ordinary strip of microfilm are approximately two inches and since the slits 50 and 51 are spaced apart a distance of only 1.9 inches, a portion of the film strip will extend beyond the slit 51 a distance of approximately 0.2 inch. Actuation of the handle 62 will act to effect a burst cut of the film by the knife 60 and will simultaneously act to effect a shear cut of the film by the knife 61. As above described, the film slug or 0.2 inch length portion of the film strip will fiy upwardly and outwardly of the shear-cutting block 68. By rotating the knob 29, the leading or forwardmost edge of the film strip will act against the rear or trailing edge of the cut film piece to push the film piece along the film bed 14 and thence into the record card pocket in the manner already described. Once the film piece has been pushed all the way into the film pocket the knob 29 can then be rotated in an opposite direction to retract the film strip from the record card and to place the film strip in the desired position for the next cutting operation. The record card with the film piece enclosed in its film pocket will then be removed from the card bed and another card can be placed thereon for insertion of another film piece in this same manner.

We have therefore disclosed a method and means for cutting film pieces into lengths less than the center-tocenter distances of adjacent images on an ordinary microfilm strip and for expelling the resulting slug and effecting this entire operation in a single step and for feeding the cut film piece into the film pocket of a record card.

It will of course be'understood that this embodiment of our invention has been used for illustrative purposes only and that various modifications and variations in the invention can be effected without departing from the spirit and scope of the novel concepts thereof.

We claim as our invention:

l. A film feed mechanism for feeding film into record card pockets formed by at least one enveloping member and mounted on a card surface which comprises:

(a) a support having a film bed and having a card bed recessed slightly from said film bed;

(b) a shoulder leading from one to the other of said beds;

(c) whereby a record card can be placed upon said card bed with an edge which is parallel to an unsecured edge of its respective enveloping member disposed in engagement with said shoulder;

(d) means confining a film strip for travel along said film bed;

(e) a pair of elongated apertures formed in spaced relationship within said support and extending transversely across said film bed,

(f) slitter blades mounted on said support for movement within said apertures,

(g) a cutting block mounted adjacent each of said apertures and over said film channel,

(h) an arcuately chamfered edge formed on at least one of said blocks,

(1') means moving said slitter blades through said apertures and into engagement with said blocks so that one of said blades slides along a side of one of said blocks adjacent said arcuately chamfered edge to cut a film strip lying Within said channel over said apertures,

() and means for moving said film strip along said film bed to push the film piece into a record card pocket.

2. A film feed mechanism for feeding film into record card pockets formed by at least one enveloping member mounted on a card surface which comprises:

(a) a support having a film channel formed therein;

(b) means feeding a film strip into said film channel;

(c) whereby a record card is positioned upon said support at one end of said film channel;

(d) a pair of slits formed in spaced relation within said support and extending transversely across said film channel;

(e) slitter blades mounted on said support for movement within said slits;

(f) cutting blocks mounted over said film channel adjacent each of said slits;

(g) a concave arcuately chamfered edge formed on at least one of said cutting blocks;

(h) means moving said slitter blades through said slits and into engagement with said blocks so that one of said blades slides along a side of one of said blocks adjacent said arcuately chamfered edge to cut a film strip lying within said film channel.

3. A film feed mechanism for feeding film into record card pockets formed by at least one enveloping member mounted on a card surface which comprises:

(a) a support having a film channel formed therein;

(b) means feeding a film strip into said film channel;

(c) means confining said film strip for sliding movement along said film channel;

(d) whereby a record card is positioned upon said support at one end of said film channel;

(e) a pair of slits formed in spaced relation within said support and extending transversely across said film channel;

(f) slitter blades mounted on said support for movement within said slits;

(g) cutting blocks mounted over said film channel adjacent each of said slits;

(h) a concave arcuately chamfered edge formed on at least one of said cutting blocks;

(i) means moving said slitter blades through said slits and into engagement with said blocks so that one of said blades slides along a side of one of said blocks adjacent said arcuately chamfered edge to cut a lrn strip lying Within said channel;

(j) whereby a cut piece of lm is moved into a record card pocket by movement of the lm strip along said film channel.

References Cited in the le of this patent UNITED STATES PATENTS Heeter Oct. 2, Schutter Sept. 11, Treis et al. Dec. 30, McArthur June 30, Engelstein May 24, Heckman Feb. 6, 

2. A FILM FEED MECHANISM FOR FEEDING FILM INTO RECORD CARD POCKETS FORMED BY AT LEAST ONE ENVELOPING MEMBER MOUNTED ON A CARD SURFACE WHICH COMPRISES: (A) A SUPPORT HAVING A FILM CHANNEL FORMED THEREIN; (B) MEANS FEEDING A FILM STRIP INTO SAID FILM CHANNEL; (C) WHEREBY A RECORD CARD IS POSITIONED UPON SAID SUPPORT AT ONE END OF SAID FILM CHANNEL; (D) A PAIR OF SLITS FORMED IN SPACED RELATION WITHIN SAID SUPPORT AND EXTENDING TRANSVERSELY ACROSS SAID FILM CHANNEL; (E) SLITTER BLADES MOUNTED ON SAID SUPPORT FOR MOVEMENT WITHIN SAID SLITS; (F) CUTTING BLOCKS MOUNTED OVER SAID FILM CHANNEL ADJACENT EACH OF SAID SLITS; (G) A CONCAVE ARCUATELY CHAMFERED EDGE FORMED ON AT LEAST ONE OF SAID CUTTING BLOCKS; (H) MEANS MOVING SAID SLITTER BLADES THROUGH SAID SLITS AND INTO ENGAGEMENT WITH SAID BLOCKS SO THAT ONE OF SAID BLADES SLIDES ALONG A SIDE OF ONE OF SAID BLOCKS ADJACENT SAID ARCUATELY CHAMFERED EDGE TO CUT A FILM STRIP LYING WITHIN SAID FILM CHANNEL. 